20459609 has 2 divisors, whose sum is σ = 20459610. Its totient is φ = 20459608.

The previous prime is 20459563. The next prime is 20459623. The reversal of 20459609 is 90695402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18088009 + 2371600 = 4253^2 + 1540^2 .

It is a cyclic number.

It is not a de Polignac number, because 20459609 - 2⁸ = 20459353 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20459629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10229804 + 10229805.

It is an arithmetic number, because the mean of its divisors is an integer number (10229805).

Almost surely, 2^20459609 is an apocalyptic number.

It is an amenable number.

20459609 is a deficient number, since it is larger than the sum of its proper divisors (1).

20459609 is an equidigital number, since it uses as much as digits as its factorization.

20459609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 35.

The square root of 20459609 is about 4523.2299300389. The cubic root of 20459609 is about 273.5053189211.

The spelling of 20459609 in words is "twenty million, four hundred fifty-nine thousand, six hundred nine".